Heat exchangers



Dec. 30, 1958 E. R. M. HOLMQUIST 2,866,624

HEAT EXCHANGERS Filed Aug. 17, 1955 4 Sheets-Sheet 1 INVENTOR [IQ/V57 Q1/0011 MAG/M9 MLMQU/ST ATTORNEYS Dec. 30, 1958 E. R. M. HOLMQUIST HEAT EXCHANGERS 4 Sheets-Sheet 2 INVENTOR ATTORNEYS Dec. 30, 1 958 E. R. M. HOLMQUIST 2,866,624

HEAT EXCHANGERS 4 Sheets-Sheet 3 Filed Aug. 17, 1955 A MN 1;: J; 3: H v J l mu .3. A

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HEAT EXCHANGERS 4 Sheets-Sheet 4 Filed Aug. 17, 1955 III [RA ST [9000M AMI/US HflZMOZl/ST ATTORNEYS Unite Sttes Patent 2,866,624 HEAT EXCHANGERS Ernst Rudolf Magnus Holmquist, Gothenburg, Sweden Application August 17, 1955, Serial No. 528,987 laims priority, application Italy August 20, 1954 6 Claims. (Cl. 257-6) The present invention relates to the class of apparatus generally described as heat exchangers and serving for transferring heat through a matrix from one fluid to another fluid.

The general object of the invention resides in the provision of a heat exchanger of this kind which is simple in design and efficient in operation as compared with previously known constructions.

For the objects stated, according to the invention, the heat exchanging matrix is in the form of a plurality of thin-gauge endless webs made of a material of high heat capacity and high thermal conductivity, said webs being passed over guide rolls and adapted, in operation to be moved continuously through chambers containing the fluids, respectively, while passing from one to the other of said chambers.

' As bands have a very large surface area inrelation to their mass, and the said areas transfer theheat, one can by driving the bands with great speed obtain good heat-transfer capacity with need only for simple governing devices and small power owing to the small weight of the-band per length and the elasticity thereof.

' There is also the advantage that the device otters-only small resistance to traveling through those media between which heat is to be exchanged.

On account of the form, of the bands and the high speed at which the bands are intended to be driven around, it is very easy to remove therefrom residues deposited by the media with the help of brushes or other scrapers, and thus inefliciency owing to such deposits can be substantially minimized.

Two specific embodiments of the invention will now be described by way of example, reference being had to the accompanying drawings in which:

Figure 1 is a perspective view of a heat exchanger incorporating the invention.

Figure 2 is a vertical section through this heat' exchanger.

Figure 3 is a horizontal section throughthe same taken along the line IlI--III in Figure 2.

Figures 4 and 5, in longitudinal and transverse crosssection, respectively, illustrate a somewhat simplified construction of a heat exchanger incorporating the invention. Referring first to the embodiment illustrated in Figures 1 to 3, reference numeral 1 designates a casing the in terior of which is divided by a'partition 2 into two chambers 3 and 4. Each such chamber 3, 4 has extending th'erethrough a cylindrical duct 5, 6, respectively, having end flanges 7 which are sealingly secured'to opposite walls of the casing 1. The spaced-parallel ducts 5 and 6 are each formed in their sides mutually remote from each other with six slots 8 extending longitudinally in spaced andsubstantially parallel interrelation, the ducts being each connected with the partition 2 at their oppositely disposed sides by means of a hollow connecting piece 9 tapering towards the partition and having inserted therein five wedge shaped blocks 10 in slightly spaced interrelation so as to form between them and in relation ,ferentially on the rolls C, D, C D

2,866,624 Patented Dec. 30, 1958 to the inner wall-surfaces of said connecting piece 9 six narrow passages 11 of a 'flat configuration extending from back to front of the casing 1. The partition 2 l1'a's extending therethrough a wide cavity 12 into the center of which the apex of the cavity of each one of th'e'corinecting pieces 9 merges.

Iournalled and sealed at each end of the upper portion of the cavity 12 are rolls 13 and 14, respectively, having arranged between them a plurality of compression coilsprings 15 which are compressed between oppositely movable rails 16 engaging the respective rolls 13, 14.' Similarly journalled and sealed'at each end of the lower portion of the cavity 12 are rolls 13 and 14', respectively, having arranged between them a plurality of compression coil-springs 15' which are compressed between oppositely movable rails 16' engaging therespective rolls 13, 14.

Secured to two oppositely disposed walls interiorly of the casing 1 and in alignment with the partition 2 are two members 17 and 18, respectively, complementing the partition and forming with the opposite edges of the partition narrow passages 19 and 20 extending, from back to front of the casing 1. Formed in each member 17, 18 in alignment with' the cavity 12 in the partition 2, is a longitudinally extending recess 21, 22 respectively, for receiving a journalled roll 23,. 24, respectively.

For transferring heat from the higher-temperature lluid passed through the duct 6 in one direction, to the lowertemperature fluid passed through the duct 5 in counterflow and intended for heat-absorption, there are provided six sets of thin-gauge endless bands or webs A, B, C, D, E and F made of steel, a copper alloy or any other metallic material having high heat capacity and thermal conductivity. The sets of Webs A to F which are moved in the sense indicated by the arrows in Figure 2, are passed in common between the rolls 13, 13', through the passages llinto the duct 5, traversing the latter andout through the slots 8 and on to six guide-rolls A, B, Cr, D, E, F. From the guide-rolls A, B, .C' the web sets A, B and C are collected on to a common guide-roll G and run in common through the passage 19 and between the rolls 14, 23 on to a guide-roll G from which latter roll they run separately over individual guide-rolls A B C and through three of the slots 8 into and through the duct 6, and from the latter through three of the passages 11 up to and in between the rolls 13, 13'. The remaining three web sets D, E and F run from the rolls 13, 13' through the passages 11, traversing the duct 5 and through the remaining slots 8 thereof. to separated guide-rolls D, E, F, from which they are collected on to a guide-roll H and runv in common from the latter through the passage 20 and between the rolls 14'. 24 and on to a guide-roll H from which they are passcd separately on to individual guide-rolls D E F through the remaining slots 8 of the duct 6 into this duct, and

from the latter through the corresponding passages 11 up to and in between therolls 13, 13', in common with the web sets A, B, C. I

Each web set, as will appear from Figure 3, comprises six webs arranged in side-by-side.interrelation, and each web in the Web sets C and D is formed with a row of perforations 25 (only one such row being shown in the drawing) engaged by rows of teeth 26 provided circumg Each guide-roll is journalled at its ends in corresponding bearings, 27

disposed at opposite lateral walls of the casing 1. Sic-- cured to one end of' the roll C projecting exteriorlyof the casing is a V-pulley serving for driving the endless webs through a V-belt 28, and mounted 'beyond said V-pulley is a toothed wheel 29 which meshes with a toothed wheel 30 secured to the end of the roll D- projecting exteriorly of the casing 1. Mounted adjacent'the inner endsof the slots8 of the duct 5, on' t he innerrwallv.

surface of the latter are scrapers in the form of angle profile bars 31 serving for the removal of impurities accumulated on the web-surfaces.

During their passage through the duct 6 the webs absorb heat from the fluid passedthrough this duct, and during their passage throughrthe duct the heat thus absorbed is communicated to the fluid passed through this duct. Owing to the fact that the webs are comparatively narrow in width, there. is no dangerof the webs being subject to warping due to the non-uniform heating thereof. Due, to the feature that, on their passing through the partition 2 and the passages 19, between the latter end of the complementary members. 17, 18, the webs are passed between the respective pairs of rolls 13, 13, 14, 23 and 14, 24, satisfactory sealing conditions will obtain enabling a considerable pressure differential to exist between the two fluids without there being any danger of leakage flow between the two sections of the heat exchanger. The heat exchanger may be equipped with means for maintaining the webs in a tensioned state in spite of varying temperature conditions.

Referring now to Figures 4 and 5 of the drawing, in the embodiment illustrated therein the matrix is formed by a single web of fine-mesh wire gauze 40. The heat exchanger comprises two chambers 41 and 42 separated by a partition 43. The chamber 41 is provided with an inlet 44 and an outlet 45, and the chamber 42 has an inlet 46 and an outlet 47. The endless wire-gauze web 40 is passed alternately over guide-rolls 48.mounted in staggered interrelation within each chamber, and runs transversely to the directions of flow of the respective fluids, as indicated by the arrows. At its top and bottom edges the partition 43 is terminated with cross-pieces 49 and 50, respectively, being provided in their upwardly and downwardly facing surfaces, respectively, with spaced corrugations extending in parallel relation to the partition. Secured by screws 51 to the casing wall above the cross-piece 49 and below the cross-piece 50, respectively, are plates 52 and 53, respectively, being provided in their surfaces facing the corresponding crosspieces 49, 50, with spaced corrugations corresponding to those of these cross-pieces. The matrix web 40 is passed between the respective cross-pieces 49, 50 and the corresponding plates 52, 53, and owing to the corrugations a satisfactory sealing action is obtained whereby the fluid in one of the chambers is prevented from leaking into the other chamber. The inlets 44 and 46 have inserted therein guide-plates 55 adapted to distribute the fluid inflows over the cross-sectional areas of the chambers 2, 42.

It is understood that the invention should not be considered as restricted to the specific embodiments hereinbefore described and as illustrated in the accompanying drawings, the same being susceptible of numerous variations and modifications without departing from the scope of the invention as defined in the appended claims.

What I claim is: p

1. An apparatus for transferring heat from one fluid to a second fluid comprising a casing, a plurality of ducts extending through said casing, a partition mounted in said casing separating the same into a pair of chambers with each having one of said ducts therethrough, said partition having lateral slots' and a longitudinal cavity, a plurality of rollers positioned in said partition cavity with opposing rollers positioned across each of said partition slots, said ducts each having a plurality of spaced openings in a side portion thereof, a plurality of rollers each rotatably mounted in one casing chamber adjacent one of said ductopenings, means providing a plurality of passageways leading, through and from an opposite side portion of each duct to one of said partition ducts, and a plurality of endless-thin-gauge webs formed of a material of high heat capacity and high thermal conductivity each extending over one of said rollers in one chamber to and through a duct opening, the duct having said opening, one

of said passageways from said duct, one of said partition slots, a second of said passageways, a second duct, an opening in said second duct, over one of said rollers in the other chamber and through a second partition slot to the first mentioned roller, the webs passing through the same partition slot being pressed together by the rollers therein preventing the passage of fluid from one chamber to the other and means for driving said webs.

2. An appartus for transferring heat from one fluid to a second fluid as claimed in claim 1 wherein said means providing a plurality of passageways each consists of a hollow connector body connecting one of said ducts with said partition and tapering inwardly from said duct to said partition and a plurality of spaced apart wedgeshaped blocks positioned in said body providing passageways for said webs leading to one of said partition ducts.

3. An apparatus for transferring heat from one fluid to a second fluid comprising a pair of ducts one for each of said fluids, a partition positioned between said ducts having a slot forming a passage for said webs between said ducts, a plurality of endless thin-guage metal webs adapted to be moved from the one of said ducts through said partition slot to the second of said ducts and back to said first duct while transferring heat from one duct fluid to the second duct fluid, means spacing said webs apart while passing through said ducts, means pressing said webs together flat side to flat side while passing through said partition slot, the total cross section of said webs when pressed together flat side to flat side and the width of said slot corresponding closely to each other so as to prevent leakage of fluid through said passage, means for guiding said webs from said second duct back to said first duct and means for driving said webs.

4. An apparatus for transferring heat from one fluid to a second fluid comprising a pair of ducts each containing one of said fluids, a partition positioned between said ducts having a slot therethrough, means connecting said ducts to said partition and having a plurality of passageways placing the interior of said ducts in communication with said partition slot, said ducts each further having a series of spaced apart openings therethrough on the side of said duct opposite to said connector passageways, a plurality of endless thin-guage metal webs adapted to be moved from one of said ducts to the second of said ducts and back to said first duct while transferring heat from one duct fluid to the second duct fluid with each web extending through one of said duct openings laterally of said ducts, each of said connector passageways and said partition slot, said partition having a cavity, opposing rollers being positioned in said part1- tion cavity at the slot therethrough for guiding said webs, resilient means being provided in said partition cavity tending to move said rollers together thus pressing said webs together flat side to flat side and preventing the flow of fluid through said slot, means for guiding said webs from said second duct back to said first duct and means for driving said webs.

5. An apparatus for transferring heat from one fluid to a second fluid comprising a casing, a pair of ducts extending through said casing, a partition mounted in said casing separating the same into a pair of chambers with each having one of said ducts therethrough, said part1- tion having'lateral' slots and a longitudinal cavity, a plurality of rollers positioned in said partition cavity with opposing rollers positioned across each of said part1tion slots, said ducts each having a plurality of spaced openings in a side portion thereof, a second plurality of rollers each rotatably mounted in one casing chamber adjacent one of said duct openings, means providing a plurality of passageways leading through and from an opposite side portion of each duct to one of said partition ducts, and a plurality of endless thin-gauge webs formed of a material of high heat capacity and high thermal conductivity each extending over one of said rollers in one chamber to and through a duct opening, the duct 2,soe,624

having said opening, one of said passageways from said duct, one of said partition slots, a second of said passageways, a second duct, an opening in said second duct, over one of said rollers in the other chamber and through a second partition slot to the first mentioned roller with the portions of said webs passing through the same partition slot being pressed together by said rollers therein preventing the passage of fluid from one chamber to the other and means for driving said webs.

6. An apparatus for transferring heat from one fluid to a second fluid as claimed in claim 5, wherein said means providing a plurality of passageways each consists of a hollow connector body connecting one of said duets with said partition and tapering inwardly from said duct to said partition and a plurality of spaced apart wedgeshaped blocks positioned in said body providing passageways for said webs leading to one of said partition ducts.

7 References Cited in the file of this patent UNITED STATES PATENTS 2,216,986 Roe Oct. 8, 1940 FOREIGN PATENTS 250,172 Great Britain Nov. 20, 1925 693,048 Great Britain June 24, 1953 706,591 Great Britain Mar. 31, 1954 

